This invention relates to a tile cutting machine and, more particularly, to a tile cutting machine comprising a supporting plate for a tile to be cut, a tool guide running over the supporting plate for a cutting tool and a swivel head which can be moved by defined angular amounts about a swivel head axis and which holds a try square. The try square has a contact bar and is provided with a measuring scale and can be slid lockingly in a straight guide of the swivel head with a guide bar. The contact bar extends at right angles to the guide bar. Additionally the swivel head has a ruler with a contact edge which runs through the swivel axis.
A tile cutting machine is the subject of DE 87 15 018.2 U1. In the prior art tile cutting machine both legs of the try square form one contact edge each for the tile to be cut. One leg of the try square is guided in a straight guide of the swivel head so that it can be clamped and that leg carries a measuring scale so that one can read the distance between the other contact edge and the swivel axis. The drawback with the prior art tile cutting machine is that the try square forms with one leg a contact edge and with its other leg projects automatically always towards the same side of the supporting plate. When one must cut the tiles at an angle or diagonally so that they are adapted, for example, to the contour of a right hand or left hand tilt angle, then the try square has to be adjusted when changing from the left to the right tilt angle, and the requisite dimension can no longer be read directly on the measuring scale of the try square, but rather a difference has to be calculated and that difference has to be set with the try square, a procedure that runs, of course, the risk of an error. It would be simpler for right and left walls or tilt angles to put the tiles to be cut on the tile cutting machine, as a function of the wall side, with the front side or the rear side up, a feature that is almost impossible, because normally it is possible to cut tiles, only by scoring their front side with a cutting tool.
The invention is based on the problem of designing the tile cutting machine in such a manner that for all possible angular or diagonal cuts the requisite dimension can be read directly on the measuring scale of the try square.
This problem is solved, according to the invention, by a total of two laterally reversed try squares for insertion into the straight guide starting from the side opposite the swivel head axis.
This design makes it possible to install selectively one or the other try square into the tile cutting machine for right or left walls or tilt angles. Thus, the dimension, measured with a rule, between the last laid tile and the edge, up to which the tile to be laid is supposed to reach, can be set directly on the try square, so that there is no need to convert dimensions. Similarly the desired angle of an angular cut can be easily set.
The range, over which the try square can be moved, can be chosen especially large, if, according to an improvement of the invention, the ruler projects beyond the swivel head in the direction of the sides, oriented in opposite directions, forms a first contact edge and has a continuous straight guide, into which the guide bar of the respective try square can be installed.
Even lengths that can no longer be read on the ruler, can be set without tedious computing and without having to resort to the additional aid of a separate rule, if both sides of the swivel head axis have a ruler with a measuring scale that begins with zero, starting from the swivel axis; and the guide bar has a measuring scale that begins with zero when its respective contact edge is above the swivel head axis.
Common angular dimensions, such as 45°, 60° or 120°, can be set on the swivel head without having to pay attention to whether the lines on a scale line up when, according to another improvement of the invention, the swivel head forms a semi-circular segment and has indexing notches on a fixed pitch circle with uniform angular spacing and when the supporting plate has a spring-loaded ball detent for dropping a ball into the individual indexing notches. Owing to this design, the swivel head drops releaseably into the most useful angular positions.
The swivel head can be locked into position in an especially simple way, if on the outside along the periphery of the swivel head a curved member, provided with an angle scale, is recessed, so as not to rotate, into the supporting plate. The curved member exhibits a graduation in the direction of the swivel head, when the swivel head has correspondingly a graduation, oriented in the direction of the curved member, and when a clamping bolt's head, aligning with the upper side of the swivel head and the curved member, sits on the two graduations. The clamping bolt, penetrating the supporting plate, is designed so as to move into a clamping position by means of a clamping device.
One advantageous design is embodied in an embodiment according to which the clamping bolt has a nut on the rear side of the supporting plate; and the clamping device has a clamping fork, which is to be slid into its clamping position between the nut of the clamping bolt and the supporting plate by means of an adjusting lever.
The invention permits various embodiments. For further illustration of its basic principle, one embodiment is depicted in the drawings and is described below.